An X-ray medical diagnostic method such as mammography is a low-dose procedure that creates one or more images of a part of a patient such as a breast thereof, which is to be examined, e.g. for detection of early stages of cancer.
The mammography diagnostic procedure generally includes obtaining two images of each of the patient's breasts, one from above and one from the side. A physician or radiologist then reviews the images of the breast, i.e., mammograms, to identify any breast cancer.
While this procedure is one of the best methods of detecting early forms of breast cancer, it is still possible for the detection of breast cancer to be missed by a physician or radiologist reviewing the mammograms. For example, breast cancer may be missed by being obscured by radiographically dense, fibroglandular breast tissue.
Tomosynthesis imaging, in which a plurality of images is acquired at different angles, has been studied in an effort to detect early forms of breast cancer. By combining the plurality of images, it is possible to reconstruct any plane in the breast being imaged that is parallel to the detector. The higher number of images is utilized, the better image quality in the reconstructed tomosynthesis images is obtained.
Angiography is a radiological method for examination of blood or lymph vessels. A catheter is inserted into the vessel e.g. by Seldinger technique and a water soluble contrast agent is injected into the vessel, after which a series of X-ray images of the vessel is taken. Examinations of arteries, veins and lymph vessels are denoted arteriography, flebography, and lymphography, respectively. Arteriography, being a commonly applied examination method, includes angiocardiography for examination of the heart, coronary angiography for examination of the coronary arteries of the heart, and aortography for examination of the aorta.
Fluoroscopy is a technology for visualizing ionizing radiation. A glass plate with a surface layer of fluorescing material, e.g. BaPt(CN)4 emits visible light when being exposed to gamma rays. Fluoroscopy is used for visualizing or frequency converting images, e.g. of high repetition rate, as taken by a high speed X-ray camera, for examination of the heart of a patient for instance.
Various line detectors for detecting ionizing radiation are known in the art. While such detectors provide for instantaneous one-dimensional imaging, two-dimensional imaging can only be performed by means of scanning the line detector, and optionally the radiation source, in a direction traverse to the one-dimensional detector array. To use such a detector in e.g. tomosynthesis, wherein a plurality of images has to be acquired at different angles would be very time consuming. For e.g. angiography, wherein time-dependent variations are observed, the situation is even worse.
A scanning-based radiation detector arrangement for two-dimensional imaging of an object is disclosed in the US patent publication No. 2003/0155519 A1. The arrangement comprises a plurality of one-dimensional detector units, each comprising an entrance slit, through which ionizing radiation as transmitted through the object is entered, and being arranged for one-dimensional imaging of the ionizing radiation, wherein the detector units are arranged in an array on a support with their respective entrance slits being parallel with each other and facing the source of the ionizing radiation. The detector arrangement further includes a rotating device for rotating the detector unit array in a plane perpendicular to the direction of the ionizing radiation, while the detector units are arranged to repeatedly detect, hence creating a series of two-dimensional images of the object.